BIOMAGNETOMETER WITH SOLID CONDUCTION COOLING

摘要

A biomagnetometer includes a magnetic field sensor including a magnetic field pickup coil (210) and a detector (211) of small electrical currents flowing within the pickup coil. A vacuum-tight enclosure (212) surrounds the sensor. The enclosure has a concavely upwardly curved first wall, with the magnetic field pickup coil located adjacent to the first wall. A vented reservoir (220) of liquefied gas is located within the enclosure, and a solid thermal conductor (218) extends from the sensor. There is a vacuum-tight thermal feedthrough by which the solid thermal conductor passes between the interior and the exterior of the enclosure. Electronic circuitry for filtering and amplifying the signals of the detector is also provided. Such a biomagnetometer is placed below the body of a reclining subject, and a second portion of the biomagnetometer can be placed above the body. In one form, the enclosures are shaped to form a cavity that receives the head of the subject therein, to achieve full head coverage of the pickup coils in the biomagnetometer.